3 Answers
3

From what I've read, they claim an aerodynamic advantage, but sometimes at the expense of extra weight. I've been told that they're recommended for flat-land riders, where aero is more important than weight, and to avoid them if any climbing is involved...

The bladed spokes on my father-in-law's bike don't appear to have more metal than the round spokes on mine, just that the metal they have is flattened out for said aerodynamic advantage.
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alesplinNov 17 '10 at 23:14